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考察以牛血清代替人血清制备标准曲线时,使用高效液相色谱法(HPLC)检测喹硫平血药浓度是否存在差异。人、牛血清制备的标准曲线在50.0~1000.0 ng·mL-1浓度范围内斜率存在差异,且在不同基质中患者血药浓度测得值有显著性差异(P<0.01)。喹硫平在2种基质中的提取回收率也存在显著性差异(P<0.01)。结果表明,HPLC法测定喹硫平血药浓度时以牛血清代替人血清作为空白基质检测存在差异性。  相似文献   
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Due to its chemical complexity, proper quality control for a Chinese medical preparation (CMP) has been a great challenge. Choosing the appropriate quality markers (Q-markers) for quality control of CMP is an important work. Best of all, the chosen Q-markers are the main chemical compounds from the herbals as well as the active constituents of this CMP. Only in this way the established quality control system can really achieve the purpose of controlling the quality of CMP and ensuring the safely and effectively use of CMP. To achieve the purpose, network pharmacology combined with the contents of chemical compounds in the CMP has been used in this research. We took an anti-arrhythmic CMP, Shenxian-Shengmai oral liquid (SSOL), as an example. Firstly, UPLC-QTOF-MS/MS method was used to analyze the main components of SSOL. A total of 64 compounds were unambiguously or tentatively identified and 32 of them were further validated by reference compounds. Secondly, the network was constructed based on the identified compounds to predict the effective compounds related to cardiac arrhythmias. Based on the existing database and the operation method of topology, a method of double network analysis (DNAA) was proposed, from which 10 important targets in the pathway of arrhythmia were screened out, and 26 compounds had good antiarrhythmic activity. Based on the prediction results of network pharmacology along with the contents of the compounds in this CMP, ten representative compounds were chosen as the Q-markers for the quality control of SSOL. We find that five of these ten compounds, including danshensu, rosmarinic acid, salvianolic acid A, epimedin A and icariin, have antiarrhythmic activity. Then, the UPLC-DAD method was established as the control method for SSOL.  相似文献   
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Abstract

Glycosylation is an effective approach to improve the druggability of natural products by increasing their water solubility. In this work, we report the glycosylation of oleanane-type triterpenoids by a recombinant microbial glycosyltransferase YjiC1. A preliminary screening test indicated YjiC1 exhibited robust capabilities for O-glycosylation of triterpenoids, based on LC/MS analysis. Among the products, two new compounds (2a and 3a), together with a known one (1a), were isolated and characterized. These products exhibited improved water solubility, and 3a showed moderate anti-HIV activities at 100 μM. This reaction provides a facile and efficient approach to synthesize the glucosides of triterpenoids.  相似文献   
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Aim

To provide a systematic review of the existing theory, framework, systems and instruments for tracing and evaluating quality in rural health services.

Subjects and methods

We searched six electronic databases up to March 2016. Observational studies of quality assessment of rural health services using theoretical models were included. Ekman’s scale was used to evaluate the quality of the included studies.

Results

A total of 18 studies, published between 2001 and 2015, met the inclusion criteria. The corresponding authors for most of them (7, 44%) are from Chinese institutions and three (3, 17%) from Australian institutions. Five studies (28%) focused on township hospitals. Primary health care quality was reported in five studies (28%), followed by clinical service in four (22%). More than half of the studies (61%) were considered of high quality, and the remainder was of moderate quality. These studies applied 16 theoretical systems, including the model/pattern (4, 25%), method/tool (7, 44%) and framework of the theory (5, 31%). Most of the theoretical models (14, 88%) obtained positive observations. In addition, the conceptual model (6, 36%) and TOPSIS method (2, 13%) were more frequently reported.

Conclusion

Although most of the current studies were considered to have high-quality and positive results, there were limitations in the number of publications and research on theoretical systems. The lacks of unified standards and comprehensive evaluation are important issues that need to be pointed out and resolved.
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目的:为进一步了解Rg3对映体的立体化学选择性,对PXR配体结合结构域(PXR ligand-binding domain,PXR-LBD)中20(R/S)-Rg3的结合模式进行建模。方法:使用计算对接,分子动力学(molecular dynamics,MD)和基本动力学分析(essential dynamics analysis,EDA)等技术手段进行建模。结果:PXR中20(S)-Rg3的MM / PB-SA估计结合能大于20(R)-Rg3。两种配合物的RMSFs表明,20(S)-Rg3结合的LBD的迁移率比20(R)型对映体的迁移率降低得多。EDA预测和两个复合物的叠加三维结构都表明20(S)-Rg3在PXR中的结合比20(R)-Rg3更可能与生物学结果一致。结论:以上结果表明,基于目前的模拟结果,PXR中20(S)-Rg3的结合模式比20(R)-Rg3更有可能与生物实验结果吻合。  相似文献   
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